Browsing Artículos by Title
Now showing items 126-145 of 200
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Narrow-band search of continuous gravitational-wave signals from Crab and Vela pulsars in Virgo VSR4 data
(2015)In this paper we present the results of a coherent narrow-band search for continuous gravitational-wave signals from the Crab and Vela pulsars conducted on Virgo VSR4 data. In order to take into account a possible small ... -
Neo y paleoornitología virtual
(2014)La visualización y análisis de los fósiles asistido por computadoras ha revolucionado el estudio de los organismos extintos. Técnicas novedosas permiten caracterizar los restos en tres dimensiones y acceder a detalles sin ... -
Neutrinos
(2015)En este artículo vamos a repasar brevemente el Modelo Estándar de Partículas, luego haremos una revisión cronológica del descubrimiento del neutrino. Por último mencionaremos el Observatorio de Neutrinos de Sudbury y ... -
Non-strongly isospectral spherical space forms
(2016)In this paper we describe recent results on explicit construction of lens spaces that are not strongly isospectral, yet they are isospectral on p-forms for every p. Such examples cannot be obtained by the Sunada method. ... -
Nonmodal linear stability of the Schwarzschild black hole
(2014)A proof is given that the space L of solutions of the linearized vacuum Einstein equation around a Schwarzschild black hole is parametrized by two scalar fields, which are gauge invariant combinations of perturbed algebraic ... -
Normal holonomy of orbits and Veronese submanifolds
(2015)It was conjectured, twenty years ago, the following result that would generalize the so-called rank rigidity theorem for homogeneous Euclidean submanifolds: let Mn, n ≥ 2, be a full and irreducible homogeneous submanifold ... -
Obstacles modelling reality: two exploratory studies on physics defined and undefined problems
(2014)One important skill to be developed in future physicists is modelling reality using physics. Problem-solving is the activity most used to teach, learn and assess physics skills at the university level. However, most of the ... -
On a mathematical theory of complex systems on networs with application to opinion formation
(2014)This paper presents a development of the so-called kinetic theory for active particles to the modeling of living, hence complex, systems localized in networks. The overall system is viewed as a network of interacting nodes, ... -
On Dirichlet problems with singular nonlinearity of indefinite sign
(2015)Let Ω be a smooth bounded domain in RN , N ≥ 1, let K, M be two nonnegative functions and let α, γ > 0. We study existence and nonexistence of positive solutions for singular problems of the form −Δu = K(x)u−α − λM (x)u−γ ... -
On homogeneous Ricci solitons
(2014)We study the evolution of homogeneous Ricci solitons under the bracket flow, a dynamical system on the space Hq,n ⊂ Λ2g∗ ⊗ g of all homogeneous spaces of dimension n with a q-dimensional isotropy, which is equivalent to ... -
On nonsingular two-step nilpotent Lie algebras
(2014)A 2-step nilpotent Lie algebra n is called non-singular if ad X : n → [n, n] is onto for any X /∈ [n, n]. We explore non-singular algebras in several directions, including the classification problem (isomorphism invariants), ... -
On stochastic spatial patterns and neuronal polarity
(2014)Polarization refers to asymmetric changes in cellular organization that occur in response to external or internal signals. Although neurons can spontaneously establish and maintain asymmetric distributions of signalling ... -
On structural completeness versus almost structural completeness problem : a discriminator varieties case study
(2015)We study the following problem: determine which almost structurally complete quasivarieties are structurally complete. We propose a general solution to this problem and then a solution in the semisimple case. As a consequence, ... -
On the evolution of the momentarily static radiation free data in the Apostolatos - Thorne cylindrical shell model
(2014-02-24)In this paper we study the evolution of the 'Momentarily Static and Radiation Free' (MSRF) initial data for the Apostolatos–Thorne cylindrical shell model. After briefly reviewing the equations of motion, the definition ... -
On the linear stability of the extreme Kerr black hole under axially symmetric perturbations
(2014)We prove that for axially symmetric linear gravitational perturbations of the extreme Kerr black hole, there exists a positive definite and conserved energy. This provides a basic criteria for linear stability in axial ... -
On the nature of defects in liquid-phase exfoliated graphene
(2014)Liquid-phase exfoliation is one of the most promising routes for large-scale production of multilayer graphene dispersions. These dispersions, which may be used in coatings, composites, or paints, are believed to contain ... -
On the theorem of the primitive element with applications to the representation theory of associative and Lie algebras
(2014)We describe all finite dimensional uniserial representations of a commutative associative (resp. abelian Lie) algebra over a perfect (resp. sufficiently large perfect) field. In the Lie case the size of the field depends ... -
One-dimensional singular problems involving the p-Laplacian and nonlinearities indefinite in sign
(2016)Let Ω be a bounded open interval, let p > 1 and γ >, and let m : Ω → ℝ be a function that may change sign in Ω. In this article we study the existence and nonexistence of positive solutions for one-dimensional singular ... -
A pair production telescope for medium-energy gamma-ray polarimetry
(2014)We describe the science motivation and development of a pair production telescope for medium-energy (∼5–200 MeV) gamma-ray polarimetry. Our instrument concept, the Advanced Energetic Pair Telescope (AdEPT), takes advantage ... -
Pensar y calcular
(2014)Pensamos. Y pensamos que pensar es una de las características distintivas de los bípedos implumes, distinción que ha provocado un salto evolutivo incalculable. A veces tratamos de calcular distintas cosas, por ejemplo ...
